We're hiring!

Linux Kernel 5.4

Enric Balletbò i Serra avatar

Enric Balletbò i Serra
December 02, 2019

Share this post:

Reading time:

Linus has released the 5.4 kernel and Collabora was once again a very active contributor to the Linux project. For this release, 12 Collaborans authored 95 commits while also helping the kernel maintainers by contributing 124 Reviewed-by tags. It's also worth mentioning that Emil Velikov joined the list of the 10 top reviewers for this release!

On the media subsytem front, Boris Brezillon and Ezequiel Garcia continued leading the work on the Hantro VPU driver, which supports video decoding on Rockchip RK3288, RK3399 and NXP i.MX8MQ SoCs. This release introduces support for H.264 decoding on RK3288, and also VP8 decoding on RK3288 and RK3399. Popular RK3288-based platforms include ASUS Chromebook Flip and ASUS C201 Chromebook, so this change brings Chromebooks one step closer to running upstream, reducing the up/downstream gap.

Recent efforts to improve upstream kernel quality, such as KernelCI and Syzbot, are now more mature, identifying bugs that open security attacks vectors. An early bug identification allows the community to fix the issues upstream, on the spot. As a result, running devices closer to upstream can be more valuable.

For this reason, the vendors and the kernel community have been working together, striving to improve the situation. Check out the Kernel Recipes 2019 presentation titled "Driving the industrytoward upstream first" for a more lengthy discussion.

Continuing with our work on Chromebooks, Chrome OS Embedded Controller platform drivers were restructured, from an architecture point-of-view. Enric Balletbò cleaned up the historical issue of having crossed references between the Multi-Function Devices (MFD) subsytem and the Chrome Platform subsystem. This allows a cleaner and easier workflow for developers to introduce the new features of future ChromeOS devices.

On the DRM front, Andrzej Pietrasiewicz merged a big part of his patchset to associate DDC adapters with connectors, standardizing its sysfs attributes. So now developers know where how to express the DDC, and product designers can rely on it. Emil Velikov audited the DRM ioctls removing misleading notations such as DRM_UNLOCKED which are not needed for recent drivers. Additionally, he purged the DRM_AUTH tag when the same ioctl is exposed via the render node. As the latter design decision implicitly invalidates the need for the tag.

On the IIO sensors side, Martyn Welch added support of the NOA1305 ambient light sensor. Fabien Lahoudere, added new properties to the Chrome OS EC sensors core.

Finally, but not least important, we continued improving the kernel by sending fixes on the issues we found. Gaël Portay, Guillaume Tucker, Helen Koike and André Almeida contributed with different patches to fix issues in the devfreq subsystem, the Virtual Video Test Driver (vivid) and the Virtual Media Controller Driver (vimc) respectively. Tomeu Vizoso, who continues working on the userspace part of Panfrost, kept an eye on the kernel side and sent a fix for the Panfrost Power Management initialization.

You can see the complete list of Collabora contributions below and check out the always interesing Kernel Newbies 5.4 page for a lot more details.

Here is the complete list of Collabora contributions:

Andrzej Pietrasiewicz (13):

André Almeida (11):

Boris Brezillon (7):

Emil Velikov (17):

Enric Balletbo i Serra (12):

Ezequiel Garcia (24):

Fabien Lahoudere (2):

Gaël Portay (2):

Guillaume Tucker (2):

Helen Koike (2):

Martyn Welch (2):

Tomeu Vizoso (1):


Alyssa Rosenzweig (1):

Boris Brezillon (23):

Emil Velikov (85):

Enric Balletbo i Serra (3):

Ezequiel Garcia (7):

Sebastian Reichel (5):


Adrian Ratiu (1):

Alyssa Rosenzweig (24):

Emil Velikov (40):

Pekka Paalanen (6):

Sebastian Reichel (4):


Boris Brezillon (11):

Dafna Hirschfeld (2):

Enric Balletbo i Serra (8):

Ezequiel Garcia (9):

Gabriel Krisman Bertazi (2):

Sebastian Reichel (26):


André Almeida (1):

Enric Balletbo i Serra (5):


Comments (0)

Add a Comment

Allowed tags: <b><i><br>Add a new comment:


Search the newsroom

Latest News & Events

WhisperSpeech makes its way to AI.dev


Collabora is headed to California to take part in the inaugural edition of AI​.dev: Open Source GenAI & ML Summit, a new event which aims…

Ready for embedded: PipeWire 1.0 released


It is with the utmost excitement that we witness the release of PipeWire 1.0, the first officially stable release of this noteworthy inter-process…

MiniDebConf Cambridge 2023


This week, the Debian project takes over Cambridge as MiniDebConf kicks off right in our own British backyard! Organized by Debian project…

Open Since 2005 logo

We use cookies on this website to ensure that you get the best experience. By continuing to use this website you are consenting to the use of these cookies. To find out more please follow this link.

Collabora Ltd © 2005-2023. All rights reserved. Privacy Notice. Sitemap.